Preheat oven to 400 and line a large baking sheet with aluminum foil, spray with cooking spray.
Chop potatoes into small chunks, place in a large Ziplock bag or bowl, set aside.
Combine olive oil, mustard, lemon juice, green onions, sugar, garlic, salt and pepper in a small mixing bowl or measuring cup.
Toss the potatoes in 2/3 of the mustard mixture.
Sprinkle the parmesan on half of the baking sheet, sprinkle potatoes directly over parmesan. (leaving the other half of the baking sheet empty for your broccoli). Bake potatoes for 25-30 minutes.
In the same Ziplock bag or bowl you tossed your potatoes in toss the broccoli with the rest of the mustard mixture.
After potatoes have roasted for 25-30 minutes remove from oven and lightly stir.
Place the broccoli on the other side of the pan,put back in the oven for 7-10 minutes until roasted. Serve with lemon wedges.